The present invention relates to a press machine to process work sheets of a wide range of material and thickness.
Press-processing including punching deals with work sheets of various thickness and material. A servo-motor-driven punch press or a hydraulic machine is capable of controlling various parameters, including ram speed curves, hover heights, and punching ton numbers. To insure high-quality processing, these parameters need to be set when necessary.
Conventionally, in an effort to automate the setting of these parameters, commands called xe2x80x9cMATxe2x80x9d have been prepared in a processing program in respect to the thickness and the material of the work sheets, so that control parameters are chosen automatically during the execution process by NC devices.
However, describing commands for specifying the work sheet thickness and material in a processing program may place additional burden on programming process. In addition, although it is preferable to vary the hover height of the ram depending on the thickness of the work sheets, it is not possible to write in a processing program to reflect these partial variations in surface height that exist in work sheets, which are likely to occur due to bending or the like.
Further, although work sheets may have protection coating such as a coating sheet or other types of coating, the types of coating vary to such a large extent that it is too burdensome to make a program if commands corresponding to each coating are written in a process program.
It is thus an object of the present invention to provide a press machine that can evaluate and identify the types of the work sheets mechanically, and further apply suitable processing in accordance with the types of the work sheets.
Another object of the present invention is to make it easier to choose control parameters.
Still another object of the present invention is to realize optimum processing.
A press machine of the present invention is composed of a processing means 3 for pressing a work sheet W; a plurality of detecting means 37xcx9c40 for detecting work sheet type specifying factors on the press machine; a work sheet type identifying means 41 for identifying the type of the work sheet W based on the factors detected by the detecting means 37xcx9c40; a control parameter selection means 42 for selecting control parameters based on the type identified by said work sheet type identifying means 41; and a process control means 32 for controlling the processing by said processing means 3 based on the control parameters that have been selected by the control parameter selection means 42. Said work sheet type specifying factors include work sheet thickness, variations in the surface height of a work sheet, material, existence of surface protection and types thereof, and other factors except for the size of the whole sheet or the shape of the whole sheet.
When a work sheet W is delivered to the press machine, the detecting means 37xcx9c40 detect a plurality of work sheet type W specifying factors. The work sheet type identifying means 41 identifies the type of the work sheet W based on the detected factors. The parameter selection means 42 selects control parameters in accordance with the type identified. The process control means 32 control the processing of the processing means 3 based on the parameters thus selected. In this way, the type of work sheet W is detected, identified on the machine, and appropriate control parameters are automatically selected. As a result, highly automated processing is made possible. In this case, the identification of work sheet W is done after detecting various factors, so that the identification of the work sheet W is done appropriately, and various types of work sheets W depending on various purposes can be identified, and high quality processing in accordance with the types of work sheets W is made possible.
In the present invention, said parameter selection means 42 is composed of a parameter memory means 44, in which types of work sheets W and control parameters are stored so that the elements of the latter are linked with the ones of the former; and a parameter selection section 43 which selects appropriate control parameters from said parameter memory means 44 based on the type of the work sheet identified by said work sheet type identifying means 41.
In this way, determining control parameters is made easy by devising a separate parameter memory means 44, which stores types of work sheets W and control parameters with elements of the latter related to the elements of the former.
In the present invention, if said processing means 3 is a punch processing means driven by a ram 5, said control parameters may include at least one of the following parameters: the speed pattern of said ram 5, the hover height of said ram 5, the press torque of said ram 5 in form processing, and the number of tons to specify the strength for punching in punching operation.
These parameters including the speed pattern, the hover height, the ram press torque in forming operation, and the number of punching tons, influence the quality and efficiency of processing. Automatic selection of said parameters by means of the parameter selection means 42 ensures optimum processing.